There’s an Aspect of Cancer Screening That Celebrities Won’t Tell You

There are all sorts of tools that help us deal with our fear of cancer, like the breast cancer risk calculator that Olivia Munn says saved her life. That’s what many women also say about mammography: “Screening saved my life.”

Risk calculators and mammography can provide some important information. But there is a lot they can’t reveal. We need to keep our faith in these tools in perspective because, although they offer a sense of hope, some of that hope is false, and that false hope can lead to great harm.

Risk calculators—like this one from the National Cancer Institute, or this one from the Breast Cancer Surveillance Consortium—allow a health care provider to estimate a woman’s breast cancer risk, based on age, medical and family history, when she first gave birth, and other factors. They give estimates for five-year and lifetime risk. The average American woman’s lifetime breast cancer risk is 8 percent. Munn’s was 37 percent.

But the calculators, which experts recommend should be used only with the guidance of a health care provider, have major limitations. They can’t accurately estimate risk for women with a history of invasive breast cancer or noninvasive ductal carcinoma in situ or for women with mutations in the BRCA1 or BRCA2 gene. Even when their estimates are accurate, the calculators cannot predict what type of breast cancer might arise. That’s critical because roughly 1 in 5 breast cancers are over-diagnosed, so slow- or even non-growing that if left alone, they would never cause symptoms during the woman’s lifetime.

Mammography, too, has its cons as well as its pros. Mammograms find more of the slow-growing, nonthreatening types, like DCIS, because there are more of them out there than the aggressive, fast-growing types, called “interval” cancers, which can arise and become life-threatening in the intervals between regular biannual mammograms. Munn had gotten an all-clear on her most recent mammogram and a negative result checking for the BRCA1 and BRCA2 genes. But her doctor ran her other factors through a risk calculator, which led to a biopsy and discovery of an interval cancer that was highly treatable. Finding it later might have been too late.

As for those slow-growing cancers that mammograms are so good at catching, many of them would never actually go on to cause harm if simply left alone. Most women with such over-diagnosed cancer have surgery anyway. Cancer is a scary beast. We fear it more than any other disease. Those lumpectomies and mastectomies are essentially “fear-ectomies” that remove something frightening but not medically threatening. Those surgeries have costs.

According to the U.S. Preventive Services Task Force, the panel of volunteer experts who make recommendations about who should undergo cancer screening, “For every woman who avoids a death from breast cancer through screening, 2 to 3 women will be treated unnecessarily.” According to figures in my book Curing Cancer-phobia: How Risk, Fear, and Worry Mislead Us, an estimated 60,000 women in the U.S. were diagnosed with DCIS in 2017. (Almost all of those cases were detected by mammography.) The vast majority of the diagnosed women, 97 percent, had some kind of surgery. One-third of those were full mastectomies. DCIS often causes no symptoms at all. But some cases (“high-grade”) have the potential to spread and cause harm. Assuming that a quarter of those mastectomies were on such riskier cases, that means in one year, a total of 13,100 women had their breasts removed for a disease that almost certainly never would have caused any harm. But the surgeries certainly did.

Roughly 35 women died as a result of those surgeries. Roughly 25 percent of those undergoing mastectomies—3,275 women—suffered post-mastectomy pain syndrome, lasting pain that can be mild or severe, that can come on immediately after the surgery or weeks or months later, and that can last a short time or a lifetime. Roughly 9 percent suffered post-surgical breast cellulitis infections causing swelling and pain; although most patients are successfully treated with antibiotics, in rare cases these infections are so severe that they require surgical treatment. And for many women, breast removal has psychosocial costs.

When they were first diagnosed, most of these women were told that their disease was slow- or non-growing and low-risk, and many were told, informally, that they might want to consider ongoing monitoring as a first step. But the professional medical groups that set standards of care require doctors to prescribe surgery as the standard treatment for DCIS, arguing that without that aggressive approach, rare cases of DCIS might kill. So, despite the women’s reassurance that their case was slow- or non-growing and low-risk, under the dark cloud of deep fear of cancer, nearly all of them choose surgery; afterward, many are certain that the surgery saved their lives, even though the disease has a lifelong survival rate of nearly 100 percent, whether treated or not.

This is just one of many ways the fear of cancer causes real and serious harm. And remember, it starts with screening, the one tool we have that gives us a sense of empowerment against a disease that many still believe to be an automatic death sentence.

But have you ever heard any of this? Over-diagnosed breast cancer that essentially poses no threat? Screening and surgery that frequently does more harm than good? Probably not. You certainly haven’t heard any of these cautions from the doctors and hospitals and cancer advocacy groups that promote screening. They all want to save lives. Most also want to make money. Mammography is a multibillion-dollar industry. So is the breast cancer testing and treatment that mammography leads to. And it is hard to imagine a celebrity gaining media attention with a story like: I have a lump in my breast, but with the guidance of my doctor I am just going to wait and see what happens with it.

Cancer is awful, an often cruel killer, the second leading cause of death in the U.S. and the disease we fear more than any other. Tools that help us find it early, when it’s more treatable, are vital and certainly do save lives like Munn’s. But all cancer screening tools, not just mammograms, have their limits and their downsides, and unless we are fully informed of their risks as well as benefits, many of us, under that dark shadow of our fear of cancer, will be making ill-informed choices that end up doing us harm.